Loan experienced a miscarriage during her first pregnancy due to undiagnosed Hashimoto's hypothyroidism, a condition where the immune system attacks the thyroid gland. At seven weeks pregnant, doctors at Tam Anh General Hospital, TP HCM, observed that her embryo had an enlarged yolk sac measuring 8 mm (normal is 3-5 mm) but no fetal heartbeat, indicating abnormal development.

Despite receiving oral medication, suppositories, and injections to sustain the embryo, the yolk sac grew to 10 mm one week later. With no fetal heartbeat, doctors confirmed a miscarriage and advised medical termination of the pregnancy.

After recovering, Loan returned to Tam Anh General Hospital, TP HCM, for a comprehensive examination to determine the cause of the miscarriage. A thyroid ultrasound revealed significantly elevated Anti-Tg levels, reaching 395 IU/mL, far exceeding the normal range of

Dr. Tram consults with Loan regarding treatment. *Photo: Tam Anh General Hospital*

Dr. Tran Nguyen Quynh Tram, Associate Head of the Endocrinology - Diabetes department, explained the critical role of Thyroglobulin (Tg). Tg is a natural protein in the thyroid gland involved in producing T3 and T4 hormones, which regulate metabolism and maintain vital bodily functions. Normally, the body does not produce antibodies against Tg.

In individuals with autoimmune thyroid disease, such as Hashimoto's or Basedow's disease, the immune system mistakenly identifies Tg as a foreign agent. It then produces Anti-Tg antibodies to attack it, causing inflammation and impaired thyroid function. This disruption is particularly problematic during pregnancy.

According to Dr. Tram, the thyroid gland is activated during pregnancy to produce sufficient hormones for both the mother and the developing baby. If the thyroid gland fails to produce enough necessary hormones, it can lead to severe complications, including miscarriage, stillbirth, or fetal growth restriction.

Following her diagnosis of Hashimoto's hypothyroidism, Loan was prescribed hormone replacement therapy. Doctors emphasized the importance of maintaining a diverse diet, controlling weight, and undergoing regular thyroid check-ups. These measures are crucial to support normal pregnancy and childbirth in the future.

For future pregnancies, doctors advised Loan to take an early pregnancy test if she suspects she is pregnant or experiences a missed period. Prompt contact with an endocrinologist is essential to adjust her medication, ensuring effective treatment and supporting normal fetal development.

By Bach Duong

*Patient's name has been changed